Different Localities of Potassium-Rich Silica-Undersaturated Igneous Rocks and Their Silica-Rich Variants - Origin of Potassium-rich Silica-deficient Igneous Rocks - page 175

Fig. 4.23 Vesuvius Volcano,
half encircled by the breached
caldera known as Monte
Somma (after Holmes 1965)

Ottajano

Observatory Crater

1906

A C
B DE G

To r r e
Breco

1906

GULF OF
NAPLES

Torre Annunziata

Pompeii

Fig. 4.24 Digramatic
representation of the growth
of Vesuvius volcanic cone
(after Holmes 1965)

1920
1918
1917
1916
1913

1915
1914

1913

1906

1906

The Vesuvian eruption often involved expulsion of magma charged with gases,
which got accumulated during a long period of quiescence and mild activity. Quite
often discharge of explosive gases through the conduit could be found, whereas
coherent lava

ows escaped through ssures and vents on the flanks. During its

explosive phases, there are vast clouds in the form of , which are

luminous during the night. This type of eruption is popularly known as Plinian type

' cauli owers '